I just bought the Concerto, and it's one serious integrated amp. I've owned a bunch of integrateds from such companies as BAT, Musical Fidelity, Krell, and several others, and the Concerto trumps them all. It's by far the quietest amp I've ever had in my room--which lets all sorts of previously unheard details in music and movies pour forth. If you're looking for tube warmth, look elsewhere, but it's far from cold or clinical. Neutral is more like it. It also has 250 WPC, which is more than almost any other integrated I can think of, save the Musical Fidelity KW500. I'm using it to drive Von Schweikert VR-4s, and it handles them pretty easily. I don't know what the Xenon's sensitivity and impedence curve look like, but the Concerto should be able to handle it. One caveat: The volume control has a very strange progression to it. I have to turn it up to almost 60 (out of 99) before I get any decent volume out of it. But once I past that point, the sound explodes, and the volume becomes much more linear. It's a weird little quirk, but hardly a deal-breaker IMO. There are a lot of other contenders in or near this price range--the aforementioned KW500 is probably the closest contender I can think of--but the Concerto ranks up there pretty highly. Super-quiet, ultra-reliable, dynamic as hell, extremely musical--I can't think of what more I would ask of an integrated amp, even at its lofty price point.
